Sign post



FIG. 1 is a perspective view of the sign post;

FIG. 2 is a front view of the sign post of FIG. 1, the rear view is a mirror image of the front view;

FIG. 3 is a right side view of the sign post of FIG. 1, the left side view is a mirror image of the right side view; and,

FIG. 4 is an enlarged top view of the sign post of FIG. 1.

The broken line disclosure is for illustrating portions of the sign post that form no part of the claimed design. 

CLAIM The ornamental design for a sign post, as shown and described. 